Fetal diagnosis of interrupted aortic arch

Usefulness of three vessel-trachea view and parasagittal plan for prenatal diagnosis of interrupted aortic arch

BACKGROUND

Interrupted aortic arch (IAA) is a rare congenital heart disease characterized by loss of continuity between the ascending and the descending aorta. Prenatal diagnosis of IAA by echocardiography is challenging but nonetheless can be accomplished via a systematization of cardiac fetal evaluation.

CASE PRESENTATION

We report a case of fetal IAA type A prenatally diagnosed through two-dimensional echocardiography using both a three vessel-trachea view and a sagittal view.

CONCLUSION

Prenatal counseling regarding the diagnosis and prognosis about this anomaly is still challenging nowadays due to associated anomalies/chromosomal abnormalities who may impact the prognosis. Fetal autopsy in all cases of pregnancy termination after abnormal ultrasound findings is important in order to make a full diagnosis and characterize the anomaly.

Unraveling the Trio of Interrupted Descending Aorta, Aortic Stenosis, and Bicuspid Aortic Valve: A Complex Cardiovascular Conundrum

Interrupted descending aorta (IDA) is an extremely rare congenital heart defect characterized by a complete loss of connection between the ascending and descending aorta. This condition is typically diagnosed in infancy or early childhood, but there have been very few cases reported in adulthood. Here, we present a unique case of an IDA in a 16-year-old patient with concomitant aortic stenosis (AS) and bicuspid aortic valve (BAV), making it an extremely rare scenario. This case highlights the importance of early diagnosis and appropriate management in patients with an IDA, particularly when in association with other cardiovascular abnormalities.

Improved Outcomes in Patients with 22q11.2 Deletion Syndrome and Diagnosis of Interrupted Aortic Arch Prior to Birth Hospital Discharge, a Retrospective Study

Interruption of the aortic arch (IAA) is a rare but life-threatening congenital heart defect if not corrected in the neonatal period. IAA type B is highly correlated with 22q11.2 deletion syndrome (22q11.2DS); approximately 50% of patients with IAA type B also have 22q11.2DS (Peyvandi et al.; Goldmuntz et al.). Early identification and repair of IAA can prevent severe morbidity and death. However, IAA is challenging to identify prenatally, or even in the neonatal period. In this study, we examined infants with IAA, diagnosed during pregnancy and prior to discharge (PPTD) from the birth hospital vs. those diagnosed following discharge (FD) from the newborn nursery. Our goals were to determine: (1) if early diagnosis improved outcomes; and (2) if patients with IAA and without 22q11.2DS had similar outcomes. In total, 135 patients with a diagnosis of 22q11.2DS and IAA were ascertained through the 22q and You Center at the Children's Hospital of Philadelphia (CHOP). The examined outcomes included: timing of diagnosis; age at diagnosis (days); hospital length of stay (LOS); duration of intensive care unit (ICU) stay; mechanical ventilation (days); duration of inotrope administration (days); year of surgical intervention; birth hospital trauma level; and overall morbidity. These outcomes were then compared with 40 CHOP patients with IAA but without 22q11.2DS. The results revealed that the PPTD neonates had fewer days of intubation, inotrope administration, and hospital LOS when compared to the FD group. The outcomes between deleted and non-deleted individuals with IAA differed significantly, in terms of the LOS (40 vs. 39 days) and time in ICU (28 vs. 24 days), respectively. These results support the early detection of 22q11.2DS via prenatal screening/diagnostics/newborn screening, as IAA can evade routine prenatal ultrasound and postnatal pulse oximetry. However, as previously reported in patients with 22q11.2DS and congenital heart disease (CHD), patients with 22q11.2DS tend to fare poorer compared to non-deleted neonates with IAA.

Preoperative Physiology, Imaging, and Management of Interrupted Aortic Arch

Interrupted aortic arch (IAA) is a rare form of critical neonatal heart disease in which there is lack of continuity between the ascending aorta and the descending thoracic aorta. In the absence of prenatal diagnosis, patients with IAA present in shock when the patent ductus arteriosus closes. Diagnosis can generally be made by echocardiography, and initiation of prostaglandin E1 infusion allows for adequate lower body perfusion prior to surgical repair. Full neonatal repair can be achieved with good outcomes in most cases. However, there is often underdevelopment of the left ventricular outflow tract and risk for later surgical re-intervention. Many patients with IAA, particularly those with type B, have DiGeorge syndrome, which has important development implications.

Does measurement of four-limb blood pressures at birth improve detection of aortic arch anomalies?

OBJECTIVE

To determine normal four-extremity blood pressure (BP) in the neonatal intensive care unit (NICU) at birth and the utility of upper (UE) and lower extremity (LE) BP difference to screen for coarctation of the aorta (Co-A) and interrupted the aortic arch (IAA).

STUDY DESIGN

Retrospective study of BP at birth (n=866), and case-control study of Co-A/IAA infants and matched controls (1:2).

RESULT

Although BP increased with gestational age (R(2)=0.3, P<0.0001), the pressure gradient between UE and LE did not change with gestation (P=0.68). Forty-six cases of Co-A/IAA were identified, with 92 controls. Pressure gradient was significantly higher in patients with Co-A/IAA (7.6±14.8 versus 0.4±10 mm Hg, P=0.004). However, there was overlap between cases and controls resulting in low sensitivity (41.3% with ⩾10 mm Hg gradient cutoff).

CONCLUSION

Evaluation of UE-LE BP gradient at birth is a poor screening test for Co-A/IAA with low sensitivity. Repeating four-limb BP after ductal closure at 24 to 48 h along with SpO2 screening for critical congenital heart disease may increase sensitivity.

Prenatal Diagnosis of Fetal Interrupted Aortic Arch Type A by Two-Dimensional Echocardiography and Four-Dimensional Echocardiography with B-Flow Imaging and Spatiotemporal Image Correlation

BACKGROUND

Fetal interrupted aortic arch (IAA) is a rare cardiac anomaly and its prenatal diagnosis is challenging. The purpose of our report is to evaluate the use of two-dimensional echocardiography (2DE) and 4D echocardiography with B-flow imaging and spatiotemporal image correlation (4D BF-STIC) in detecting IAA type A (IAA-A).

MATERIALS & METHODS

Twenty-three cases of confirmed IAA-A identified by fetal echocardiography were involved in the study. The fetal echocardiography image data were reviewed to analyze the ratio of right ventricle to left ventricle (RV/LV) diameter, the ratio of main pulmonary artery to ascending aorta (MPA/AAO) diameter, and the correlation of RV/LV diameter ratio and size of ventricular septal defect (VSD). 4D BF-STIC was performed in 21 fetuses using the sagittal view (4D BF-STIC-sagittal) and the four-chamber view (4D BF-STIC-4CV) as initial planes of view. An additional 183 normal fetuses were also included in our study. RV/LV and MPA/AAO ratios were calculated and compared with that of IAA-A fetuses. Fetal 2DE, 4D BF-STIC-sagittal, and 4D BF-STIC-4CV were used to visualize the aortic arch and its associated neck vessels. Six subgroups were evaluated according to gestational age.

RESULTS

Fetal 2DE, 4D BF-STIC-sagittal, and 4D BF-STIC-4CV made the correct prenatal diagnosis of IAA-A in 19/23 (82.6%), 14/21 (66.7%), and 19/21 (90.5%) of patients, respectively. A significantly enlarged MPA combined with symmetric ventricles was found in the IAA-A fetuses, while the size of the VSD was negatively correlated with RV/LV ratio. 4D BF-STIC-sagittal and 4D BF-STIC-4CV were better than traditional 2D ultrasound in detecting the aortic arch and neck vessels between 17 and 28 gestational weeks and 29 to 40 gestational weeks in normal fetuses.

CONCLUSION

It is demonstrated that IAA-A could be diagnosed by traditional fetal echocardiography, while 4D technique could better display the anatomic structure and the spatial relationships of the great arteries. Use of volume reconstruction may promote its clinical usage and help prenatal diagnosis.

The three-vessel view in the fetal mediastinum in the diagnosis of interrupted aortic arch

Interruption of the aortic arch (IAA) is difficult to detect and diagnose in utero. However, prenatal diagnosis may be beneficial because IAA is rapidly fatal (median age, 10 d) if left uncorrected. Our objective was to review the direct and indirect echocardiographic markers associated with IAA, focusing on the importance of the three-vessel view (3VV), which is obtained during routine ultrasound examination to rule out malformations. We analyzed the fetal echocardiograms of nine fetuses and compared them with 56 normal controls. In each fetus, there was a large discrepancy between the diameter of the larger, dilated pulmonary artery (PA) and smaller, narrow aortic arch (Ao). The calculated ratio of PA/Ao in fetuses with IAA was 2.6 ± 0.4 compared with 1.1 ± 0.09 in normal controls (p < 0.0001). The calculated ratio of PA/Ao in fetuses with IAA type A was 2.1 ± 0.09 and IAA type B 2.9 ± 0.2 (p = 0.0007). Discrepancy between PA/Ao diameters should raise the suspicion of aortic arch anomalies and a large discrepancy is a nearly pathognomonic sign of IAA type B.

Comparison of cardiac Z-score with cardiac asymmetry for prenatal screening of congenital heart disease

OBJECTIVE

To determine the best screening tests for discriminating early indicators of cardiac hypoplasia in congenital heart disease (CHD) from normal variations in fetal cardiac growth.

METHODS

We retrospectively examined fetal echocardiograms from 90 infants with confirmed CHD: Group 1 (n = 35) with right-sided obstructive lesions and Group 2 (n = 55) with left-sided obstructive lesions. Our control group comprised 2735 normal fetuses, from which we determined fetal cardiac Z-scores of right ventricle (RV), left ventricle (LV), aorta (Ao) and pulmonary artery (PA) diameters and ratios of right to left ventricle (RV:LV) and pulmonary artery to aorta (PA:Ao) size. We compared our control group to Groups 1 and 2 using ANOVA and area under receiver-operating characteristics curve (AUC) analysis.

RESULTS

For Group 1, RV:LV ratio, RV-Z-score and PA:Ao ratio were the best screening tests, with highest AUCs (0.879, 0.868 and 0.832, respectively). For Group 2, the Ao-Z-score, PA:Ao and RV:LV ratios were the best screening tests, with AUCs of 0.770, 0.723 and 0.716, respectively.

CONCLUSION

None of the screening tests was found to be a perfect early discriminator for the cardiac lesions tested. Although ratios of PA:Ao and RV:LV are useful, they should be combined with fetal cardiac Z-scores to maximize screening sensitivity.